With continuous development of broadband wireless communications technologies, mobile broadband traffic in the future will be more than a thousandfold of current mobile broadband traffic. To meet the development, using a high frequency band having a high rate and high bandwidth to perform data communication is bound to become a development trend of a broadband wireless communications system. FIG. 1 is a schematic diagram of an architecture of a high frequency network. As shown in FIG. 1, the high frequency network includes: one macro base station, a user equipment (UE), and multiple small cells (including a serving small cell performing data communication with the UE) in a coverage area of the macro base station. A small cell may perform data service transmission with the UE by using a high frequency band.
Compared with a low frequency signal, a high frequency signal has a severer transmission loss and a poorer penetration capability. Therefore, with impact of factors such as blocking of a building, blocking of a human body, and misalignment of a high frequency signal beam, the UE is extremely easily located in a coverage hole of the serving small cell. Consequently, a high frequency signal received by the UE is too poor to be demodulated, or the UE fails to receive a high frequency signal sent by the serving small cell, thereby affecting quality of receiving a high frequency service by the UE and a probability that the UE receives the high frequency service. Therefore, when the UE is in the coverage hole of the serving small cell, a corresponding measure needs to be taken, to reduce a probability that receiving a high frequency service by the UE is interrupted, and maintain continuity of data communication.
To resolve the foregoing problem, currently, in a high frequency network communications system, when the UE is in a coverage hole of a serving small cell, the UE performs synchronous measurement on all high frequency beams of all small cells around the UE by using an initial synchronous measurement method, selects an optimal small cell and beam pair for re-access, and receives high frequency data sent by the small cell, ensuring continuity of high frequency data communication. However, in this implementation method, the UE needs to perform synchronous measurement on all the beams of all the small cells, complexity is relatively high, and a synchronous measurement time is relatively long, thereby leading to a relatively large delay of re-access of the UE to another small cell, and reducing quality of service (QoS) of the UE.